Heat exchange system with inclined heat exchanger device

ABSTRACT

A technique for cooling an air flow through a heat exchanger device involves a controlled change of direction from an air input direction to cooling fins in the heat exchanger device. The heat exchanger device is angled relative to the air stream input direction. The heat exchanger device may include a fluid-carrying conduit, a plurality of sets of cooling fins coupled along the fluid-carrying conduit, and a plurality of air stream deflectors, coupled to the fluid-carrying conduit, that form dividers between the sets of cooling fins. In operation, the air stream deflectors may change in a controlled manner air stream direction from the air stream input direction into a direction approximately parallel with the cooling fins and, after passing out of the cooling fins, change in a controlled manner air stream direction to an air stream output direction.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Application claims the benefit of U.S. Provisional Application No. 60/674,782 filed on Apr. 25, 2005, which is incorporated by reference.

BACKGROUND

Heat exchangers are used to remove heat from, for example, electronic systems. Typically, the heat exchangers have a size limitation. For example, some electronic systems are located within a cabinet, so the heat exchangers must fit inside the cabinet. While it is generally accepted that more size will enable greater heat exchange, making high capacity heat exchangers that fit within a small space is an ongoing challenge.

In a typical heat exchanger, an air flow passes over or through the heat exchanger, through some passages that allow contact between the air and a heat exchanger coil, and out the other end. Heat exchangers may include thin metal fins that are fastened so that their planes are oriented normally to the axis of a heat exchanger coil. One technique that has yielded some success in reducing the vertical height of a high capacity heat exchanger is inclining the heat exchanger in the direction of the air flow. Unfortunately, the incline forces the air flow to make two changes in direction, one down into the fins and one horizontally out of the inclined heat exchanger. The resistance to air streams incident at acute angle to the plane of the fins may cause a pressure drop across the heat exchanger assembly, introduce turbulence in the air flow, reduce air flow, or raise the pressure required to drive the air flow through the core.

The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.

SUMMARY

The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools, and methods that are meant to be exemplary and illustrative, not limiting in scope. In various embodiments, one or more of the above-described problems have been reduced or eliminated, while other embodiments are directed to other improvements.

A technique for cooling an air flow through a heat exchanger device involves a controlled change of direction from an air input direction to cooling fins in the heat exchanger device. A system according to the technique includes a duct, a fan, and a heat exchanger device. In operation, the fan directs an air stream through the duct in an air stream input direction. The heat exchanger device is angled relative to the air stream input direction. The heat exchanger device may include a fluid-carrying conduit, a plurality of sets of cooling fins coupled along the fluid-carrying conduit, and a plurality of air stream deflectors, coupled to the fluid-carrying conduit, that form dividers between the sets of cooling fins. In operation, the air stream deflectors may change in a controlled manner air stream direction from the air stream input direction into a direction approximately parallel with the cooling fins and, after passing out of the cooling fins, change in a controlled manner air stream direction to an air stream output direction.

A heat exchanger device according to the technique may include heat exchanger coils, a plurality of director vanes coupled to the heat exchanger coils, and a plurality of fins coupled to the heat exchanger coils in subpluralities that are arranged substantially in parallel between the director vanes. In operation, conditioned cooling fluid may pass through the heat exchanger coils and absorb and carry away heat from the fins. In operation, air may flow in an air input direction against a first director vane, the first director vane may change the direction of the air flow to approximately parallel to a subplurality of fins, the air flow may pass between the subplurality of fins, the subplurality of fins may absorb heat from the air flow, the air may flow against a second director vane, and the second director vane may change the direction of the air flow to an air output direction that is approximately parallel to the air input direction and approximately perpendicular to the subplurality of fins.

A method for building a heat exchanger device according to the technique may include providing a tube, stacking a plurality of fins onto the tube, interspersing a plurality of director vanes between subpluralities of fins, and pressurizing the tube to tighten the tube against the fins and director vanes.

The proposed system can offer, among other advantages. These and other advantages of the present invention will become apparent to those skilled in the art upon a reading of the following descriptions and a study of the several figures of the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention are illustrated in the figures. However, the embodiments and figures are illustrative rather than limiting; they provide examples of the invention.

FIG. 1 depicts a conceptual view of an example of a system with a heat exchange mechanism.

FIGS. 2A and 2B depict an example of a heat exchanger assembly for use in the system of FIG. 1.

FIGS. 3A and 3B depict an example of a heat exchanger device for use with the heat exchanger assembly of FIGS. 2A and 2B.

FIG. 4 depicts a cross-sectional view of a heat exchanger device in a heat exchange system.

FIG. 5 depicts an alternative heat exchanger assembly with fins approximately parallel to an air stream input direction.

FIG. 6 depicts an example of a fin that is suitable for use with the assembly of FIG. 5.

FIG. 7 depicts an example of a fin that is suitable for use with the assembly of FIG. 5.

FIG. 8 depicts a flowchart of a method for cooling air with an inclined heat exchanger device.

FIG. 9 depicts a flowchart of a method for constructing a heat exchanger device.

DETAILED DESCRIPTION

In the following description, several specific details are presented to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention can be practiced without one or more of the specific details, or in combination with other components, etc. In other instances, well-known implementations or operations are not shown or described in detail to avoid obscuring aspects of various embodiments of the invention.

FIG. 1 depicts a conceptual view of an example of a system 100 with a heat exchange mechanism. In the example of FIG. 1, the system 100 includes an enclosure 110, an electronic assembly 120, and a heat exchange system 130. The example of FIG. 1 is intended to illustrate a system 100 in which heat is removed from the enclosure 110 by way of the heat exchange system 130.

The enclosure 110 may be, by way of example but not limitation, a cabinet, a compartment, a room, or some other structure that encloses the electronic assembly 120 and the heat exchange system 130. In practice it is found that the greatest need for heat exchangers is in enclosed spaces. Indeed, space inside the enclosure 110 is sometimes at a premium. Nevertheless, in alternative embodiments, the system 100 need not be enclosed.

The electronic assembly 120 may include any equipment that would potentially have performance degradation if the equipment overheated and/or any electronic equipment that generates heat. The electronic assembly 120 may include electronic data equipment that is used, by way of example but not limitation, for high speed Internet, for streaming data services, as data center servers, and/or in the telecommunications industry. Other known or convenient uses would be apparent to those of skill in the relevant art.

In the example of FIG. 1, the heat exchange system 130 includes one or more fans 132 and a heat exchanger assembly 134. In an embodiment in which space is at a premium inside the enclosure 110, it may be desirable to minimize the size, particularly the vertical height, of the heat exchange system 130.

The one or more fans 132 move air from the enclosure 110 into the heat exchanger assembly 134. As used herein, a fan refers to any type of air distribution device. The fans 132 may simply be configured to direct air out of the enclosure 110 into the heat exchanger assembly 134, or the fans 132 may associated ducts that cause air to be moved from a particular part of the enclosure 110, such as relatively near a heat-producing portion or heat-susceptible portion of the electronic assembly 120. Despite the apparent location in a given drawing, fans may be placed in any convenient location to facilitate air flow into and/or out of a heat exchanger device. In another embodiment, fans may be located at both ends of the heat exchanger assembly 134 to simultaneously direct air into and away from the heat exchanger assembly 134. In another embodiment, fans may also be located above the electronic assembly 120 to direct air downward toward the heat exchange system 130. In another embodiment, some fans may also be used to direct air out of the enclosure 110. Other known or convenient uses of fans would be apparent to those of skill in the relevant art.

In the example of FIG. 1, the heat exchanger assembly 134 includes a duct 136 and a heat exchanger device 138. The heat exchanger assembly 134 may be fluid-cooled. A fluid-cooled heat exchanger typically has fluid-carrying conduits (not shown) that are connected to a fluid source and sink (not shown). In operation, fluid flows through the coils, and air passing through the heat exchanger assembly 134 transfers some of its heat to the fluid, which may be water, direct expansion gas, or some other known or convenient fluid, and is removed from the enclosure 110 to a remote heat sink (not shown), such as air outside of the enclosure 110. The fluid may be conditioned in some way. By way of example but not limitation, water may include glycol and/or rust inhibitors, which can improve coolant characteristics, improve the lifespan of the device through which the fluid flows, or provide other known or convenient benefits. A treated fluid may be referred to generally as a conditioned cooling fluid.

The duct 136, as depicted in FIG. 1, appears to be the same length as the inclined heat exchanger device 138. However, the duct 136 may be longer or shorter than the heat exchanger device 138. The duct 136 may be of any appropriate shape or size, and made of any known or convenient material. In operation, air from the fans 132 enters the duct in an air stream input direction that is, for illustrative purposes only, depicted in FIG. 1 as an arrow from the fans 132 into the duct 136.

It may be advantageous to affix the heat exchanger device 138 to the duct 136 such that no air passes between the duct 136 and the heat exchanger device 138, thereby forcing all of the air to pass through the heat exchanger device 138 at some point. The passage of air through the heat exchanger device 138 is depicted in FIG. 1, for illustrative purposes only, as an S-shaped arrow. The S-shaped arrow is intended to illustrate the controlled direction change of the air flow using techniques described later with reference to FIG. 2.

The heat exchanger device 138, as depicted in FIG. 1, appears to be inclined at about 45° to the horizontal. However, the angle of incline may vary between 0° and 90°. The incline can serve to increase the surface area of fluid-carrying conduits and/or cooling fins presented to the incident air stream. However, the incline forces air flow to make two potentially large changes in direction, which can restrict the flow of air from a given set of fans and limit the heat removal capacity of the heat exchanger assembly 134. Thus, the advantages of inclination must be balanced against issues such as back pressure from air flow direction change, turbulence, and other factors, or these issues must be counteracted in some manner.

Although FIG. 1 depicts only one of the heat exchange system 130, multiple heat exchange systems could be placed within the enclosure 110. Similarly, multiple heat exchange assemblies could be used within the heat exchange system 130. Similarly, multiple heat exchange devices could be used within the heat exchange assembly 134.

FIGS. 2A and 2B depict an example of a heat exchanger assembly 200 for use in the system 100 (FIG. 1). In the example of FIG. 2A, the heat exchanger assembly 200 includes a housing 202, a drain 204, manifolds 206 (only one of which is visible in FIG. 1), and a heat exchanger device 208. FIG. 2B provides an alternative view of the heat exchanger assembly 200 with the top of the housing 202 removed for illustrative purposes. FIGS. 2A and 2B are intended to illustrate a high capacity air-to-fluid heat exchanger, such as by way of example but not limitation the type of heat exchanger used in fluid-cooled cabinets for data center servers.

In the example of FIGS. 2A and 2B, the housing 202 forms a duct, such as the duct that is conceptually depicted in FIG. 1. The drain 204 is used to drain condensated water out of the housing 202. Though the drain 204 is optional, it has been found that the drain 204 is valuable in implementations typical of the heat exchangers described herein.

In the example of FIGS. 2A and 2B, the manifolds 206 may serve as an inlet and outlet for fluid. In an embodiment, an input manifold of the manifolds 206 is coupled to one end of the heat exchanger coils 212 and an output manifold of the manifolds 206 is coupled to the other end of the heat exchanger coils 212. The size of the manifold depends upon the requirements of the system. For example, in a specific implementation, the manifolds 206 are about ¾″ tubes with fittings to which conduits to a fluid source and sink can be affixed.

In the example of FIGS. 2A and 2B, the heat exchanger device 208 is mounted within the housing 202 at an angle that is inclined relative to the housing opening. The heat exchanger device 208 includes director vanes 210 and heat exchanger coils 212. The director vanes 210 direct air that enters the duct in an air input direction into the heat exchanger device 208. The director vanes 210 cause the air to change direction in a controlled manner to reduce, for example, back pressure and turbulence. Further description of the controlled direction change is provided with reference to FIG. 3.

In the example of FIGS. 2A and 2B, there are 13 heat exchanger coils 212 coupled to the director vanes 210. As used herein, a heat exchanger coil is any known or convenient mechanism for flowing fluid into the heat exchanger device, and then flowing the fluid away. There may be more or fewer than 13 heat exchanger coils 212, depending upon the implementation. The shape of the heat exchanger coils (e.g., round, oval, square, etc.), the number of loops in a coil, and other considerations may vary widely depending upon what is considered convenient or advantageous for a particular implementation. In an embodiment, the director vanes 210 act as cooling fins for the heat exchanger coils 212, and absorb heat from the air flowing through the heat exchanger device 208.

In operation, the heat absorbed by the director vanes 210 is conducted to the heat exchanger coils 212. Alternatively or in addition, the heat exchanger coils 212 absorb heat from the air flowing through the heat exchanger device 208. In either case, whether the heat is absorbed by the heat exchanger coils 212 directly or indirectly through the director vanes 210, fluid passing through the heat exchanger coils 212 absorbs and carries away heat from the air flowing through the heat exchanger device 208. The fluid enters the heat exchanger device 208 from a fluid source (not shown) via an in-manifold of the manifolds 206 and exits the heat exchanger device 208 to a fluid sink (not shown) via an out-manifold of the manifolds 206.

FIGS. 3A and 3B depict an example of a heat exchanger device 300 for use with the heat exchanger assembly 200 (FIGS. 2A and 2B). The heat exchanger device 300 includes director vanes 310, heat exchanger coils 312, and cooling fins 314. The director vanes 310 and heat exchanger coils 312 are similar to those described with reference to FIGS. 2A and 2B. The cooling fins 314, more easily visible in FIG. 3B, which represents portion 320 of the heat exchanger device 300, are arranged in sets between the director vanes 310.

In the example of FIG. 3B, the cooling fins 314 appear to be shorter and thinner than the director vanes 310. This need not be the case. However, the taller, thicker director vanes 310 could protect the cooling fins 314 from deformation from, for example, impact because they are sturdier and at least partially cover the cooling fins 314. It may also be noted that more cooling fins 314 could fit within a given width if the cooling fins 314 are relatively thin. Despite these advantages, the director vanes 310 need not be thicker than the cooling fins 314, and could even be thinner. The exact thickness of the director vanes 310 and the cooling fins 314, and the relative thickness, is an implementation detail. In an embodiment, the director vanes 310 act as cooling fins, and may be more effective than, as effective as, or less effective than the cooling fins as a cooling element.

In the example of FIG. 3B, there are seven cooling fins between two director vanes. However, any number of cooling fins could be located between the director vanes. In an embodiment, more than one cooling fin is so located. It may be that too many cooling fins between director vanes reduces the effectiveness of the director vanes 210 in accomplishing a controlled direction change of an air flow. However, since the director vanes 310 help reduce back pressure so that less power is required for the fans to get a given amount of air through the heat exchanger device 300, it may be possible to put more cooling fins 314 within a given width than would be recommended in prior art implementations. Accordingly, it may be desirable to have up to approximately 70 cooling fins between director vanes. More cooling fins, or none at all (where the director vanes act as cooling fins), could be used in alternative embodiments, but with possible reduced beneficial effect. Those of skill in the relevant art, with this application before them, may be capable of determining an optimal number of cooling fins for a given application.

FIG. 4 depicts a cross-sectional view of a heat exchanger device in a heat exchange system 400. In the example of FIG. 4, the system 400 includes a housing 402, a heat exchanger device 408, director vanes 410, coils 412, and cooling fins 414, all of which have been described above and are not described in more detail here. FIG. 4 is intended to illustrate air expansion as it enters into the cooling fins 414.

In the example of FIG. 4, the gap 422 between director vanes 410, where air is intaken, is narrower than the gap 424 just before the air flows between the cooling fins 414. Advantageously, air expands between the gap 422 and the gap 424 and may flow relatively uniformly into each of the cooling fins 414. The air reaches the gap 426 after passing between the cooling fins 414, and passes through the gap 428. The gap 428 is narrower than the gap 426, so the air contracts and is exhausted. When the air is exhausted, this causes air to be more effectively pulled in through the gap 422. In an embodiment, the gaps 422 and 428 are roughly the same size, and the gaps 424 and 426 are roughly the same size. However, in alternative embodiments, the gap sizes could be adjusted to create known or convenient air flow effects.

FIG. 5 depicts an alternative heat exchanger assembly 500 with fins approximately parallel to an air stream input direction. When cooling fins are placed parallel to the air inflow direction, an air flow can pass straight through the heat exchanger without as much back pressure as compared to when the cooling fins are perpendicular to the air inflow direction.

In the example of FIG. 5, the heat exchanger assembly 500 includes an in-manifold 510, an out-manifold 520, tubes 530 coupled to the in-manifold 510 and the out-manifold 520, and fins 540 coupled to the one or more tubes 530. Relatively cool water enters the heat exchanger assembly 500 through the in-manifold 510. The relatively cool water flows from the in-manifold 510 through the tubes 530 where the fins 540 remove the heat from the enclosure (not shown). The relatively cool water absorbs the heat, making the water relatively warm. The relatively warm water moves through the tubes 530 to the out-manifold 520, and out of the enclosure to a remote heat sink (not shown). In various embodiments and/or implementations, conditioned water or some fluid besides water may be used.

The heat exchanger assembly 500 may be effective to reduce restriction to an air stream as it passes through an inclined heat exchanger device. The fins 540 of the heat exchanger assembly 500 may be affixed so that their planes are at an acute angle to the tubes 530 which convey the cooling fluid. This may reduce the resistance to the air flow, thus allowing a greater flow and an increase in the capacity of the heat exchanger assembly 500. The fins 540 may be parallel, or nearly so, to the incident air stream. Alternatively, the fins may be affixed at an angle less than 45°, or at least less than 90°.

It may be noted that the example of FIG. 5 does not appear to include any director vanes. This is because the embodiment shown has cooling fins that are approximately parallel to the input air flow. In an embodiment where the cooling fins are not parallel, it may be desirable to include director vanes.

FIG. 6 depicts an example of a fin 600 that is suitable for use with the assembly of FIG. 5. The fin 600 includes openings 602. The openings 602 are oval in shape to allow an inclined tube to be inserted therein. Obviously, if the tube were not round, the shape of the oval may have a different appearance. For example, a square tube would fit into a rectangular opening. The fin 600 is configured to accept two rows of tubes. One row of tubes may be for an inflow of fluid and the other row of tubes may be for an outflow of fluid. However, any convenient configuration could be used for a given implementation, including but not limited to a single row of tubes per fin.

FIG. 7 depicts an example of a fin 700 that is suitable for use with the assembly of FIG. 5. The fin 700 includes openings 702. For illustrative purposes only, two openings 702 are shown; there could be as many openings as tubes that pass through the fin, twice that number if each fin accepts the inflow tube and outflow tube, or some other number of openings per fin that is determined to be convenient for a given implementation. The openings 702 include a flange 704 and a hole 706. A tube passing through the opening 702 occupies the hole 706 with at least a portion of its volume, and passes through the flange 704.

Other fin configurations could be used instead of those illustrated by way of example in FIGS. 6 and 7. It should be understood that any fin configuration that is convenient for a given implementation is considered to be within the scope of the teachings provided herein.

FIG. 8 depicts a flowchart 800 of a method for cooling air with an inclined heat exchanger device. This method and other methods are depicted as serially arranged modules. However, modules of the methods may be reordered, or arranged for parallel execution as appropriate. FIG. 8 is intended to illustrate a method wherein air director vanes are used to direct air through a heat exchanger in a controlled manner.

In the example of FIG. 8, the flowchart 800 starts at module 802 where an air stream is received in an air stream input direction. The air stream may be directed toward a heat exchanger device using any type of air distribution device. The air stream may or may not be uniform, but relatively turbulent-free air may result in improved air flow. The air stream is typically warm because the heat exchanger is used to cool the air. However, the air stream could be of any temperature and the heat exchanger could be used to change the temperature of the air stream to make it cooler or warmer.

In the example of FIG. 8, the flowchart 800 continues at module 804 where air stream direction is changed in a controlled manner from the air stream input direction into a direction approximately parallel with cooling fins of a heat exchanger device. Changing direction in a controlled manner can be accomplished in a variety of ways, including but not limited to, gradually changing air direction, smoothly changing air direction, or incrementally changing air direction.

The amount of change of air direction over a given distance is an implementation decision, but the change of direction should be accomplished in a sufficiently controlled manner to reduce air turbulence and improve air flow to the cooling fins. The amount of change in air direction may depend upon the angle of the cooling fins, the incline of the heat exchanger device, or other factors. For example, the air flow direction may gradually change by 90°, 87°, or some other angle.

In the example of FIG. 8, the flowchart 800 continues at module 806 where air stream direction is changed in a controlled manner to an air stream output direction. The air stream output direction may or may not be parallel to the air stream input direction. The angle, relative to the air stream input direction and the cooling fins, is an implementation decision. As with module 806, the direction change is controlled to avoid turbulence or back pressure.

FIG. 9 depicts a flowchart 900 of a method for constructing a heat exchanger device. FIG. 9 is intended to illustrate a method wherein air director vanes are interspersed with cooling fins. Advantageously, the placement of the director vanes and cooling fins is easily accomplished with existing assembly and tooling technology. This can reduce the cost and time of R&D and other production factors.

In the example of FIG. 9, the flowchart 900 starts at module 902 where a tube is provided. The tube may be, by way of example but not limitation, part of a heat exchange coil.

In the example of FIG. 9, the flowchart 900 continues at module 904 where a plurality of fins are stacked onto the tube. The fins may have an opening that the tube fits into. Such an opening may be, by way of example but not limitation, a hole, gap, aperture, slit, or some other opening that is effective to allow a tube to pass between at least two points of the opening. Embossing may be applied around each opening (or at some other place on each fin) to ensure proper spacing between the fins.

In the example of FIG. 9, the flowchart 900 continues at module 906 where a plurality of director vanes are interspersed between subpluralities of the plurality of fins. Advantageously, the director vanes can be stacked in the same manner as the fins, and (if applicable) may be similarly embossed.

In the example of FIG. 9, the flowchart 900 ends at module 908 where the tube is pressurized to tighten the tube against the fins and director vanes. The tube may be pressurized by closing one end of the tube and pumping a fluid into the other end of the tube until the tube expands. The expansion should cause the fins and the director vanes to become relatively tightly affixed to the tube at the openings.

As used herein, the term “embodiment” means an embodiment that serves to illustrate by way of example but not limitation.

It will be appreciated to those skilled in the art that the preceding examples and embodiments are exemplary and not limiting to the scope of the present invention. It is intended that all permutations, enhancements, equivalents, and improvements thereto that are apparent to those skilled in the art upon a reading of the specification and a study of the drawings are included within the true spirit and scope of the present invention. It is therefore intended that the following appended claims include all such modifications, permutations and equivalents as fall within the true spirit and scope of the present invention. 

1. A system comprising: a duct; a fan, in communication with the duct, wherein, in operation, the fan directs an air stream through the duct in an air stream input direction; a heat exchanger device, coupled to the duct and angled relative to the air stream input direction, the heat exchanger device including: a fluid-carrying conduit; a plurality of sets of cooling fins coupled along the fluid-carrying conduit; a plurality of air stream deflectors, coupled to the fluid-carrying conduit, that form dividers between the sets of cooling fins, wherein, in operation, the air stream deflectors change in a controlled manner air stream direction from the air stream input direction into a direction approximately parallel with the cooling fins and, after passing out of the cooling fins, change in a controlled manner air stream direction to an air stream output direction.
 2. The system of claim 1, wherein the air stream output direction is approximately parallel to the air stream input direction.
 3. The system of claim 1, wherein, in operation, the air stream deflectors produce less turbulent and more uniform input velocity in an air stream passing through the duct in the air stream input direction.
 4. The system of claim 1, wherein, in operation, the air stream deflectors produce less turbulent and more uniform output velocity in an air stream passing through the duct in the air stream output direction.
 5. The system of claim 1, wherein the plurality of air stream deflectors also act as cooling fins.
 6. The system of claim 1, wherein the duct has a vertical height of less than about 8.75 inches.
 7. The system of claim 1, wherein the heat exchanger device is longer than the height of the duct.
 8. The system of claim 1, further comprising a heat sink, wherein fluid passes through the fluid-carrying conduit, absorbs heat through the cooling fins, and is directed to the heat sink.
 9. A device comprising: heat exchanger coils; a plurality of director vanes coupled to the heat exchanger coils; a plurality of fins coupled to the heat exchanger coils in subpluralities that are arranged substantially in parallel between the director vanes, wherein, in operation, conditioned cooling fluid passing through the heat exchanger coils absorbs and carries away heat from the fins; wherein, in operation, air flows in an air input direction against a first director vane, the first director vane changes the direction of the air flow to approximately parallel to a subplurality of fins, the air flow passes between the subplurality of fins, the subplurality of fins absorb heat from the air flow, the air flows against a second director vane, and the second director vane changes the direction of the air flow to an air output direction that is approximately parallel to the air input direction and approximately perpendicular to the subplurality of fins.
 10. The device of claim 9, wherein the subplurality of fins includes at least two fins arranged in parallel between the first director vane and the second director vane.
 11. The device of claim 9, wherein the subplurality of fins includes no more than 70 fins arranged in parallel between the first director vane and the second director vane.
 12. The device of claim 9, wherein the subplurality of fins includes a number of fins, and wherein the number of fins depends upon the angle between the air flow and fin faces.
 13. The device of claim 9, wherein two subpluralities of fins and the first director vane extend approximately one inch along the heat exchanger coils.
 14. The device of claim 9, wherein a liquid coolant or direct expansion gas passes through the heat exchanger coils and cools the air when the air flow contacts the heat exchanger coils.
 15. The device of claim 9, wherein the first director vane gradually changes the air flow direction.
 16. The device of claim 9, wherein the first director vane changes the air flow direction incrementally.
 17. The device of claim 9, wherein the first director vane reduces back pressure by gradually changing the air flow direction.
 18. The device of claim 9, wherein the director vanes also act as cooling fins.
 19. A method comprising: providing a tube; stacking a plurality of fins onto the tube, wherein the tube is passed through an opening in each of the plurality of fins; interspersing a plurality of director vanes between subpluralities of fins, wherein the tube is passed through an opening in each of the plurality of director vanes; pressurizing the tube to tighten the tube against the fins and director vanes at the openings.
 20. The method of claim 19, further comprising spacing the fins by providing embossing around the hole of each of the plurality of fins. 